Knocking, power loss, flashing CEL...f**k

[ThunderbirdJunkie]

I look forward to hear about the re-build when completed.
I would agree with the "borrowed time" over 100k syndrome.

Then how do you explain the plethora of 3.7s with over 200,000 on them?

 

[Marlon_JB2]

Yes I've seen way more 200k+ 3.7s than dead ones.

 

[kb0nly]

Yes I've seen way more 200k+ 3.7s than dead ones.

Same here!!

One of the main reasons i went with the KJ when looking for mid sized SUV's is that the 3.7L came so highly recommended by mechanics i know, and looking around online i saw a pretty good track record of KJ's for sale used with 150-200k on them without any major problems. If that many are making it to 200k i don't think they are in self destruct mode after 100k.

I know two KJ's here in the same town as me that are over 100k, one is at 150k+ and the other is somewhere around 180k the last time i saw it, he is a traveling salesman for a national company and prefers to drive then fly, for all i know he could be close to 200k now as i haven't seen him in person in about four months, and that can be a lot of miles for him per month. I know he has replaced his radiator a couple times along the way, and tensioner and belt, water pump, alternator, but the engine itself hasn't been opened up at all.

 

[nzoliver]

Hi all,

Engine failures on the 3.7 and the big brother 4.7 are unheard of here except for the odd one that has been abused. Many have done 150000km or more and no problems. Servicing is the key and the correct fluids etc.
I had read of problems with Volvo autos too untill I found out they WERN'T using the Volvo fluid (or the same stuff from ESSO or Mobil). The auto shops put in Dex4 and an additive "to do the same job". Only it didn't! Another stripdown and rebulid with the admitedly very expensive fluid and looky there...no problems. Go figure.....
The dealers here ONLY use the Mopar engine oil and they atribute the longevity a lot to that.

But...I will be watching mine. I have a Scangauge on mine and I have 1 reading showing the water temp. Wow1.gif

Happy days....I hope...

 

[loves_off_roading]

I heard that there have been some moderate problems with the 02 engines. A few bad apples I guess. I'm hoping to get 150+ out of my engine. If I don't I'll be really dissapointed.

 

[ThunderbirdJunkie]

lol
ThunderbirdJunkie will cry...and seriously cry...if he has a powertrain failure, major or minor, before 300,000 miles.

He is ready to accept valve springs and timing chain/tensioners...but anything beyond that is unacceptable for any engine.

150k...shit...ThunderbirdJunkie has 149,600 on his KJ now...no signs of lettin up

 

[jnaut]

Then how do you explain the plethora of 3.7s with over 200,000 on them?

They're Canadian motors... all measured in Kilometers. mj.gif

 

[moparman]

I bought mine based on 2 friends' experiences, both over 100k miles. My one friend finally traded his in with 197K miles, still shiny and running good. He bought another one, a new 2009 KK Limited. My other friend still has hers, over 120K and problem free. (I hope.)

 

[moparman]

It's been suggested before that valve rotation doesn't happen untill 3000 RPM. Maybe some people drive too easy. I definitely keep the cobwebs out of mine.

 

[jnaut]

Not going to harp on the oil changes but it could have accelerated the problem.


Ever change the coolant? Since HOAT coolant in our KJ's is based off of Ethylene Glycol it shares the one big disadvantage of it also,electrolysis(goggle it).Granted it takes longer for it to happen with HOAT but still will happen and very prone in a alloy head/cast iron block engine and kills head gaskets,more so the metal ones like our engines use.

#1 reason why I have flushed my coolant 4 times in 8 years and 70,000miles.

Amazing what a low-mileage Jeep you have. I mean, what do you only drive it to the auto parts store to buy more oil and coolant?

 

[Midgear]

Whats with all the sudden deaths of the 02' KJ's lately??

Budke - Did you ever get a solid answer as to what failed that took your motor out?

Prospect - Will be watching anxiously to see what failed in yours as well.

I'm starting to wonder about the 02's, thats two on here that died, and i have seen a few 02's on eBay with blown motors. Would be a good idea to determine whats causing it, maybe some preventative maintenance can prevent it from happening to others.

Hell if I know but I have an 02' as well and its got well over 120k on the clock, and it runs like a top. It seems to eat oil at an alarming rate, but the coolant looks fine, it doesn't smoke, clank, tick (aside from a fresh cold start at anything below freezing, even then it only lasts for about 10 seconds), it's got large amounts of power, and she purrs like a.. very fat feline.

Not sure where the oil is going, but she doesn't produce any noticeable smoke and the coolant looks nice and clean from what I can tell.. sucked some up into an antifreeze tester to check temperature handling and it looks nice and clear.. and green.

I rattle on about how great it runs.. and watch- I'm gonna go start it here in about an hour to go home from work and the engine will catch fire and fall from underneath the hood eek2.gif

 

[tjkj2002]

Amazing what a low-mileage Jeep you have. I mean, what do you only drive it to the auto parts store to buy more oil and coolant?

Well it sat in storage for a total of 2 years(2 one year deployments),that kept the mileage down,and I have no life and rarely go anywhere.


As far as "being on borrowed time" after 100k on a 3.7(any year) is 100% totally false.Just remember there are about 1 million 3.7 KJ's and god knows how many RAM's/Dakota's/Durango's/WK's that have the same 3.7.These forums breed false behaviors and longevity of stuff and only repersent far less then 0.1% of the total # of vehicles of the same make/model and engine so you will hear about a higher # of failures since poeple come on these boards and complain.You rarely ever here about the success stories.I've worked on many 4.7's with over 200k,and even a few 3.7's with over 200k and they all still ran good.Just remember the internet is not the best place to research vehicle dependability since 99% of the stuff you will find is all negative for any make/model.

 

[LibertyTC]

I still say you are on borrowed time after 100,000 miles or 160,000 km. Lets put it another way, you have done well if you get there without any failures especially on gaskets & springs w/ aluminum heads.
There is just too many variables and potential manufacturing defects, as well as driver behavior and questionable maintenance by many owners. ( I am not implying us we are informed and care enough to do good maintenance)
How many hours and revolutions has that engine turned at 100,000 miles?
Chrysler Canada offered a 7 year or 115,000 km (70K Mile) warranty.

 

[ThunderbirdJunkie]

The only variable is maintenance, barring any catastrophic abnormalities.

ThunderbirdJunkie's KJ works hard, so it likes to PLAY hard. There is not a single day that goes by that the little 3.7 isn't wrung out, hanging the ass end out around a corner or getting kicked down to 2nd gear to haul ass around some idiot driving slow.

149,6xx miles and have not had to crack the valve covers.

More than ThunderbirdJunkie could say about his 4.0 I6
his 258I6
His AMC 360
Any of the many Ford 5.0s
Ford 3.8s
Chevy 3.1s, 2.8s, and Buick 3.8s
Honda D15
Honda CVCC1800
Toyota 5EFE
Mitsubishi 6G72 SOHC

Never before has ThunderbirdJunkie had such a great, trouble-free, worry-free engine in his life. All his engines have been treated the same way.
startin to understand?

 

[LibertyTC]

You have done Very Well then, considering you drive hard. That does say something good about your maintenance and YOUR motor.

 

[tjkj2002]

I still say you are on borrowed time after 100,000 miles or 160,000 km. Lets put it another way, you have done well if you get there without any failures especially on gaskets & springs w/ aluminum heads.
There is just too many variables and potential manufacturing defects, as well as driver behavior and questionable maintenance by many owners. ( I am not implying us we are informed and care enough to do good maintenance)
How many hours and revolutions has that engine turned at 100,000 miles?
Chrysler Canada offered a 7 year or 115,000 km (70K Mile) warranty.

Having aluminum heads has nothing to do with early failure.The most high strung engines in the world are all alloy(top fuel dragsters/funny cars),puts the same stress on the engine in 4 second pass as does driving 100k,goes 2-3 passes before rebuild,and rarely ever has a top end failure(mostly spark plug failures,nothing mechanical with engine).Never had a issue with the alloy heads on my Olds 350,went over 100,000miles and was driven extremely hard(spent most of it's life well above 6000rpm's) with .750" lift cam and 13.5:1 compression ratio.

 

[ridenby]

188,882m ,if someone will buy the gas will come pick them up,and we will ride out to Cali and watch the "King of the Hammers" race in feb.

 

[ThunderbirdJunkie]

Having aluminum heads has nothing to do with early failure.The most high strung engines in the world are all alloy(top fuel dragsters/funny cars),puts the same stress on the engine in 4 second pass as does driving 100k,goes 2-3 passes before rebuild,and rarely ever has a top end failure(mostly spark plug failures,nothing mechanical with engine).Never had a issue with the alloy heads on my Olds 350,went over 100,000miles and was driven extremely hard(spent most of it's life well above 6000rpm's) with .750" lift cam and 13.5:1 compression ratio.

Jeez that's some big numbers for an Olds SB.
You use a diesel block?

 

[kb0nly]

Hell if I know but I have an 02' as well and its got well over 120k on the clock, and it runs like a top. It seems to eat oil at an alarming rate, but the coolant looks fine, it doesn't smoke, clank, tick (aside from a fresh cold start at anything below freezing, even then it only lasts for about 10 seconds), it's got large amounts of power, and she purrs like a.. very fat feline.

Not sure where the oil is going, but she doesn't produce any noticeable smoke and the coolant looks nice and clean from what I can tell.. sucked some up into an antifreeze tester to check temperature handling and it looks nice and clear.. and green.

I rattle on about how great it runs.. and watch- I'm gonna go start it here in about an hour to go home from work and the engine will catch fire and fall from underneath the hood eek2.gif

Green?? Why do you have that crap in your KJ?? HOAT only...

Any signs of oil leakage around the oil filter or oil pressure sender?

 

[jnaut]

Green?? Why do you have that crap in your KJ?? HOAT only...

X2. Change that ASAP or there's a radiator swap in your future.